Timekeeping is the practice of measuring and recording the passage of time. The shadow cast by a simple stick or obelisk allowed ancient people to keep time by observing the movement of the sun. As the sun moves across the sky, the shadow cast by a vertical object will change in length and direction. By marking the position of the shadow at regular intervals, ancient people could create a sundial, which could be used to tell the time of day.
Sundials were one of the earliest forms of timekeeping devices, and they were used for centuries before the development of mechanical clocks. Sundials are still used today as a way to teach children about the movement of the sun and the passage of time.
